Question

A car on a straight track is traveling at 20 m/s. If the car accelerates for 3 seconds at 5 m/s2, what will be the car's speed at the end of the acceleration?

A. Vf = 40 m/s
B. Vf = 35 m/s
C. Vf = 25 m/s
D. Vf = 30 m/s

Answer 1

The car's speed after accelerating for 3 seconds at a rate of 5 m/s², starting from 20 m/s, is 35 m/s.

Step-by-step explanation:

To determine the car's speed at the end of the acceleration, we use the basic kinematic equation for acceleration:

v = u + at

Where:

• v is the final velocity
• u is the initial velocity (20 m/s)
• a is the acceleration (5 m/s2)
• t is the time (3 seconds)

Plugging in the values:

v = 20 m/s + (5 m/s2 × 3 s) = 20 m/s + 15 m/s = 35 m/s

Therefore, the correct answer is B. Vf = 35 m/s.